Programmable small form-factor pluggable module

ABSTRACT

A small form factor pluggable (“SFP”) transceiver for use in a communications network includes a transmitter adapted to be coupled to the network for supplying signals to the network, a receiver adapted to be coupled to the network for receiving signals from the network, and a programmable signal processing module coupled to the transmitter and the receiver and adapted to be programmed from a remote station coupled to the network. The module can be programmed to perform at least one service or management function on the network.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application incorporates by reference in their entireties thefollowing applications, all of which have the same filing date as thepresent application: “Systems and Methods of Detecting and Assigning IPAddresses to Devices with ARP Requests,” by Robitaille and Lemieux,Attorney Docket No. 268665-000020USPT; “Systems and Methods of UsingBeacon Messages to Discover Devices Across Subnets,” by Robitaille andBouffard, Attorney Docket No. 268665-000021USPT; “Systems and Methods ofDiscovering and Controlling devices without Explicit Addressing,” byRobitaille and Bouffard, Attorney Docket No. 268665-000022USPT and“Systems and Methods of Installing and Operating Devices withoutExplicit Network Addresses,” by Robitaille and Lemieux, Attorney DocketNo. 268665-000023USPT.

FIELD OF THE INVENTION

This invention is directed towards the use of an SFP for the purpose ofoffering Service OAM functions. For ease of deployment, the SFP canoperate without any previous knowledge of the network where it isdeployed and the behaviour of the SFP and the services it can offer canbe managed in a centralized manner or distributed manner.

BACKGROUND OF THE INVENTION

An SFP is a compact, hot-pluggable transceiver used for bothtelecommunication and data communications applications. It generallyinterfaces a network device mother board (for a switch, router, mediaconverter or similar device) to a fiber optic or copper networkingcable. SFP transceivers are designed to support SONET, Gigabit Ethernet,Fibre Channel, and other communications standards. The followingdescription is based on an optical SFP, but it should be understood tocover any type of SFPs.

SUMMARY OF THE INVENTION

In accordance with one embodiment, a small form factor pluggable (“SFP”)transceiver for use in a communications network includes a transmitteradapted to be coupled to the network for supplying signals to thenetwork, a receiver adapted to be coupled to the network for receivingsignals from the network, and a programmable signal processing modulecoupled to the transmitter and the receiver and adapted to be programmedfrom a remote station coupled to the network, the module beingprogrammable to perform at least one service and management functions onthe network. The programmable signal processing module may be a fieldprogrammable gate array or an application specific integrated circuit.

In specific implementations, the programmable signal processing moduleis programmable to perform at least one service assurance function onthe network. such as monitoring network traffic and diagnosing issues(e.g., performing remote in-service Layer 1-4 loopback, ITU-T Y.1564 andRFC-2544 performance testing), and/or monitoring actual customerstatistics from a web browser or portable test set. The programmablesignal processing module may also be programmable to perform servicemanagement functions on the network, such as policing, traffic shapingand VLAN mapping.

The programmable signal processing module may be programmed to listen totraffic on the network, to detect a predetermined message broadcast by aremote device coupled to the network, and to respond to thepredetermined message to indicate that the module is coupled to thenetwork and is functioning. Communications with the remote device may bewithout the use of IP protocols over an ISO Layer 2 network.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may best be understood by reference to the followingdescription taken in conjunction with the accompanying drawings.

FIG. 1 is a diagrammatic illustration of an SFP optical transceiver.

FIG. 2 is a diagrammatic illustration of an SFP optical transceiver thatincludes an inline programmable module such as a FPGA.

FIG. 3 is a diagrammatic illustration of an adapter device that includesan SFP optical transceiver that further includes an inline programmablemodule such as a FPGA.

FIG. 4 is a diagrammatic illustration of a system in which an SFPoptical transceiver located at a network node with an FPGA that isprogrammed from a remote node.

FIG. 5 is a diagrammatic illustration of a system similar to that ofFIG. 4 in which the FPGA is configured as an embedded traffic generator.

FIG. 6 is a diagrammatic illustration of a system similar to that ofFIG. 4 in which the FPGA is configured to perform intelligent loop back.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

Although the invention will be described in connection with certainpreferred embodiments, it will be understood that the invention is notlimited to those particular embodiments. On the contrary, the inventionis intended to cover all alternatives, modifications, and equivalentarrangements as may be included within the spirit and scope of theinvention as defined by the appended claims.

Turning now to the drawings and referring first to FIG. 1, an SFPoptical transceiver module 100 houses an optical transmitter 101 and anoptical receiver 102, as per FIG. 1. The optical transmitter 101generally comprises components for generating an optical signal (e.g., alight source, such as a light-emitting diode (LED) or laser diode) andone or more optics elements for directing the light into the end of atransmit optical fiber. The optical receiver 102 generally comprises thecomponents for receiving an optical signal (e.g., a photodetector orphotosensor) and one or more optics elements for directing light outputfrom the end of a receive optical fiber onto the photodetector orphotosensor. The optics elements of the transmitter and receiver of themodule are part of an optics assembly 103 that couples to a duplexreceptacle. There is also an electrical interface 104 that includesconnections to provide power, ground and signals to the SFP. Althoughthese modules have some rudimentary monitoring capability (e.g., I2C)that are generally limited to the physical characteristics such aspower, they are by nature limited to the local physical link. Thesemodules do not have the diagnostic capabilities that are required toidentify and isolate network issues, such as delay or loss spanning theentire or a portion of the network.

FIG. 2 illustrates an optical SFP transceiver module 200 that is thesame as the module 100 with the addition of a Field Programmable GateArray (FPGA) 205. The FPGA can be added to the SFP housing, eitherinline as depicted in FIG. 2, or as an adaptor device. FIG. 3 depicts anwhere the adaptor device 301 that contains an FPGA 302 and an SFP 303and plugs into a port 304.

Additional power and a power converter may be added to the SFP to feedthe FPGA. The FPGA may initially contain some programming, but can alsobe configured and/or re-programmed from a remote station or node withoutrequiring changes to the software on the network node where the SFP withthe FPGA resides. The FPGA can also be operated remotely from a remotestation or node. The FPGA may be replaced with other programmablemodules such as ASIC-based solutions.

Since the objective is to manage the FPGA remotely without having tomodify the software or firmware on the node it resides, there is a needfor discovering that the SFP housing an FPGA has been connected on thenetwork.

In one embodiment, the FPGA on the SFP is programmed to perform serviceassurance functions on the network, such as monitoring network trafficand diagnosing issues, performing remote, in-service Layer 1-4 loopback,ITU-T Y.1564 and RFC-2544 performance testing, 1-way delay and jittermeasurements, and monitoring actual customer statistics from aweb-browser or portable test set without the need of any other testequipment, loopback testing, service management and demarcation. TheFPGA can also be programmed to perform service management functions suchas policing, traffic shaping, VLAN mapping etc.

If power consumption on the SFP is an issue, the unit can be configuredwith a subset of the functionality that complies with the powerlimitations. The set of features can be reprogrammed remotely on anas-needed basis without affecting the node or taking the port out ofservice. For example, using different FPGA loads, the on-board storagecan support multiple such loads. Loads with lesser functions can run atlower clock speed and therefore consume less power, or they may simplyhave less logic active at a time. Other techniques for increasing theefficiency of a load that are known in the art can also be applied.

The FPGA can be configured remotely while the port is active. Afterproper identification of the remote programming node, to preventsecurity breach, the FPGA collects and assembles configuration packetsinto binary files, checks the integrity of the files, and thenreprograms itself.

FIG. 4 illustrates an embodiment in which a node 401 is configured withseveral standard SFP ports 404 and one SFP port 402 with a programmableFPGA 403. All the ports 402 and 404 are connected to one or morenetworks 405 using a respective link 406. The FPGA 403 is discovered andconfigured and optionally programmed remotely by a node 407 using acontrol path 408.

FIG. 5 illustrates an embodiment in which a node 501 is configured withseveral standard SFP ports 504 and one SFP port 502 with a programmableFPGA 503. All the ports 502, 504 are connected to one or more networks505 using a respective link 506. The FPGA 503 is discovered andconfigured and optionally programmed remotely by a node 507 using acontrol path 508. In this case, the FPGA is configured as an embeddedtraffic generator 510 to create test packets 509 for insertion in thepaths of the standard SFPs 504. In this case, the port hosting the FPGA502 may be a normal forwarding port, or it could be only used to house atest traffic generator.

Referring to FIG. 6, in another embodiment, a node 601 is configuredwith several standard SFP ports 604 and one SFP port 602 with aprogrammable FPGA 603. All the ports 602, 604 are connected to one ormore networks 605 using a respective link 606. The FPGA 603 isdiscovered and configured and optionally programmed remotely by a node607 using a control path 608. In this case, the FPGA is configured toperform intelligent loop back 610 by swapping MAC and IP addresses andreturning the packets in the paths 609 of the standard SFPs 604. In thiscase, the port hosting the FPGA 602 may be a normal forwarding port orit could be only used to house the device providing loop backcapability.

The FPGA or other programmable module can be discovered in the networkusing a discoverer (e.g. testing unit, router, remote node) that islocal to the subnet where the programmed module is located. The moduleto be discovered is programmed to watch for responses of a devicelocated upstream.

The FPGA or other programmable module can be reprogrammed remotely toperform other functions or services. A discoverer can transmit amanagement packet to the FPGA or other programmable module to requestthat it loads different firmware or program logic from local permanentstorage or from a remote location. This is achieved by virtue of adual-stage boot method. When the FPGA or other programmable module needsto load new firmware or program logic, it will indicate this inpermanent storage (for instance a FLASH memory) and/or special hardwareregister to guide the primary boot loader where to locate the secondaryboot.

The present invention includes systems having processors to providevarious functionality to process information, and to determine resultsbased on inputs. Generally, the processing may be achieved with acombination of hardware and software elements. The hardware aspects mayinclude combinations of operatively coupled hardware componentsincluding microprocessors, logical circuitry, communication/networkingports, digital filters, memory, or logical circuitry. The processors maybe adapted to perform operations specified by a computer-executablecode, which may be stored on a computer readable medium.

The steps of the methods described herein may be achieved via anappropriate programmable processing device, such as an externalconventional computer or an on-board field programmable gate array(FPGA) or digital signal processor (DSP), that executes software, orstored instructions. In general, physical processors and/or machinesemployed by embodiments of the present invention for any processing orevaluation may include one or more networked or non-networked generalpurpose computer systems, microprocessors, field programmable gatearrays (FPGA's), digital signal processors (DSP's), micro-controllers,and the like, programmed according to the teachings of the exemplaryembodiments of the present invention, as is appreciated by those skilledin the computer and software arts. Appropriate software can be readilyprepared by programmers of ordinary skill based on the teachings of theexemplary embodiments, as is appreciated by those skilled in thesoftware arts. In addition, the devices and subsystems of the exemplaryembodiments can be implemented by the preparation ofapplication-specific integrated circuits or by interconnecting anappropriate network of conventional component circuits, as isappreciated by those skilled in the electrical arts. Thus, the exemplaryembodiments are not limited to any specific combination of hardwarecircuitry and/or software.

Stored on any one or on a combination of computer readable media, theexemplary embodiments of the present invention may include software forcontrolling the devices and subsystems of the exemplary embodiments, fordriving the devices and subsystems of the exemplary embodiments, forprocessing data and signals, for enabling the devices and subsystems ofthe exemplary embodiments to interact with a human user, and the like.Such software can include, but is not limited to, device drivers,firmware, operating systems, development tools, applications software,and the like. Such computer readable media further can include thecomputer program product of an embodiment of the present invention forperforming all or a portion (if processing is distributed) of theprocessing performed in implementations. Computer code devices of theexemplary embodiments of the present invention can include any suitableinterpretable or executable code mechanism, including but not limited toscripts, interpretable programs, dynamic link libraries (DLLs), Javaclasses and applets, complete executable programs, and the like.Moreover, parts of the processing of the exemplary embodiments of thepresent invention can be distributed for better performance,reliability, cost, and the like.

Common forms of computer-readable media may include, for example, afloppy disk, a flexible disk, hard disk, magnetic tape, any othersuitable magnetic medium, a CD-ROM, CDRW, DVD, any other suitableoptical medium, punch cards, paper tape, optical mark sheets, any othersuitable physical medium with patterns of holes or other opticallyrecognizable indicia, a RAM, a PROM, an EPROM, a FLASH-EPROM, any othersuitable memory chip or cartridge, a carrier wave or any other suitablemedium from which a computer can read.

While particular embodiments and applications of the present inventionhave been illustrated and described, it is to be understood that theinvention is not limited to the precise construction and compositionsdisclosed herein and that various modifications, changes, and variationsmay be apparent from the foregoing descriptions without departing fromthe spirit and scope of the invention as defined in the appended claims.

1. A small form factor pluggable transceiver for use in a communicationsnetwork, said transceiver comprising a transmitter adapted to be coupledto said network for supplying signals to said network, a receiveradapted to be coupled to said network for receiving signals from saidnetwork, and a programmable signal processing module coupled to saidtransmitter and said receiver and adapted to be programmed from a remotestation coupled to said network, said module being programmable toperform at least one service and management functions on said network.2. The small form factor pluggable transceiver of claim 1 in which saidprogrammable signal processing module includes a field programmable gatearray.
 3. The small form factor pluggable transceiver of claim 1 inwhich said programmable signal processing module includes an applicationspecific integrated circuit.
 4. The small form factor pluggabletransceiver of claim 1 in which said programmable signal processingmodule is programmable to perform at least one service assurancefunction on said network.
 5. The small form factor pluggable transceiverof claim 4 in which said at least one service assurance function isselected from the group consisting of monitoring network traffic anddiagnosing issues, performing remote in-service Layer 1-4 loopback,ITU-T Y.1564 and RFC-2544 performance testing, and monitoring actualcustomer statistics from a web browser or portable test set.
 6. Thesmall form factor pluggable transceiver of claim 1 in which saidprogrammable signal processing module is programmable to perform servicemanagement functions on said network.
 7. The small form factor pluggabletransceiver of claim 6 in which said service management functions areselected from the group consisting of policing, traffic shaping and VLANmapping.
 8. The small form factor pluggable transceiver of claim 1 inwhich said programmable signal processing module is programmable tolisten to traffic on said network.
 9. The small form factor pluggabletransceiver of claim 1 in which said programmable signal processingmodule is programmable to detect a predetermined message broadcast by aremote device coupled to said network.
 10. The small form factorpluggable transceiver of claim 9 in which said programmable signalprocessing module is programmable to respond to said predeterminedmessage to indicate that said module is coupled to said network and isfunctioning.
 11. The small form factor pluggable transceiver of claim 9in which said programmable signal processing module is adapted tocommunicate with said remote device without the use of IP protocols overan ISO Layer 2 network.
 12. The small form factor pluggable transceiverof claim 1 in which said network is an optical network and said signalsare optical signals.